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Notes Basic XML-RPC server

<?
php // this is the function exposed as “multiply( )” function times ($method, $args)
{
return $args[0] * $args[1];
}

$request = $HTTP_RAW_POST_DATA;
if (!$request) $request_xml = $HTTP_POST_VARS[‘xml’];
$server = xmlrpc_server_create( );
if (!$server) die(“Could not create server”);
xmlrpc_server_register_method($server, ‘multiply’, ‘times’);

$options = array(‘output_type’ => ‘xml’, ‘version’ => ‘auto’);
echo xmlrpc_server_call_method($server, $request, null, $options);
xmlrpc_server_destroy($server);

?>
The xmlrpc extension handles the dispatch for you. That is, it works out which method the
client was trying to call, decodes the arguments and calls the corresponding PHP function, and
returns an XML response that encodes any values returned by the function that can be decoded
by an XML-RPC client.
Create a server with xmlrpc_server_create( ):
$server = xmlrpc_server_create( );

Expose functions through the XML-RPC dispatch mechanism using xmlrpc_server_register_
method( ):

xmlrpc_server_register_method(server, method, function);
The method parameter is the name the XML-RPC client knows. The function parameter is the
PHP function implementing that XML-RPC method. In the case of above Example, the multiply
( ) method is implemented by the times( ) function. Often a server will call xmlrpc_server_
register_method( ) many times, to expose many functions.
When you have registered all your methods, call xmlrpc_server_call_method( ) to do the
dispatching:

$response = xmlrpc_server_call_method(server, request, user_data [, options]);
The request is the XML-RPC request, which is typically sent as HTTP POST data. We fetch that
through the $HTTP_RAW_POST_DATA variable. It contains the name of the method to be
called, and parameters to that method. The parameters are decoded into PHP data types, and
the function (times ( ), in this case is called). A function exposed as an XML-RPC method takes
two or three parameters:
$retval = exposed_function(method, args [, user_data]);
The method parameter contains the name of the XML-RPC method (so you can have one PHP
function exposed under many names). The arguments to the method are passed in the array
args, and the optional user_data parameter is whatever the xmlrpc_server_call_method( )’s

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